Automatic die press



June I 1927 'c. D. McDONALD {33340 AUTOMATIC DIE PRESS Filed Jai1.2O. 1926 s Sheets-Sheet 1 iii/6716071 (M7265 Z 4/ 30/2. (21d 1 1,633 340 June. 1927' c. D. M DONALD I AUTOMATIC DIE PRESS Filed Jan. 20, 19 26 3 Shanta-Shut 2 T0 CLUTCH rmwwma ARM; YLINDER 1 ,6 4 June 21,1927. an MCDONALD 1 333 0 AUTOMATIC DIE PRESS .Filed Jan.20, 1926 3 Sheets- 5km; 3

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in the feed way.

Patented June 21, 1927.

'UNITED. STATES PATENT OFFICE. ii

CHARLES :0. MCDONALD, or CHICAGO, rumors, ASSIGNOR 'ro MCDONALD m m 00., or CHICAGO, rumors, A conronarron oa ILLINOIS.

AUTOMATIC DIE PRESS.

Application filed January 192e.- Serial No. 82,395.

matic die presses, but more particularly to that type of press shown and described 1n my prior Patents No. 1,252,278 dated January 1, 1918, and No. 1,529,031 dated 'March 10, 1925, to which reference is hereinafter made.

In presses of this type, metal strips are" fed, one at a time, from a stack of strips to a feed way, in which the strip is fed forward to the dies, in a step by step fashion, by suitable finger bar mechanism, and sometimes two strips are accidentally inserted into the feed way at the same time, which results in imperfect work, and sometimes a single strip becomes buckled and jammed in the feed way. One object of the present invention is to provide automatic press stopping mechanism, which is automatically set in motion when an abnormal number of strips is placed in the feed way. Inasmuch as the metal strips'operated upon by the press are very thin, extreme sensitivenessis required of the setting mechanism, for the press stopping mechanism, sinceitis desired that the press operate continuously whileunder normal conditions, but that'when two strips are accidentally inserted into the feed way, or when one strip becomes jammedtherein the press stopping mechanism shall be .set into operation instantaneously to thereby stop the press immediately after the abnormal condition arises. Anotherobject is to provide mechanism for thispurpose which is simple, inexpensive, reliable and not likely to get out of order. Vith these and other objects and advantages in view, this invention consists in automatic press stopping mechanism, controlled by the presence of an abnormal number of strips in the feed way or by an abnormal condition of a metal strip The invention further consists in the several novel features hereinafter fully set forth and claimed. w

The invention is clearly'illustrated in the accompanying drawings, in which v Fig. 1 is a view partly in side elevation partly in vertical cross section of an automatic die press of common and well known form, stripped of much of the operating mechanism for the purpose of clarity, and illustrating a simple embodiment of the present invention applied to the press; Fig. 21s

a view'looking in the direction of the arrow 2 in Fig. ,1 of the mechanism, forming the subject matter of this'sp'ecification; Fig.3 is a face View looking in the direction of the arrow 3 in Fig. 1, and partly in section, of the finger bar mechanism, its actuating mechas nism and certain members of the pressstop-v ping mechanism forming the subject matter of this specification; Fig. 4' is a detail section taken on the line t4 of Fig. 1;-Fig. 5 is a detail section through an air valve used in the press stopping mechanism; Fig. 6 is an enlarged detail cross section 7 showing the feed way of the press and certain membeis of the press stopping mechanism; F ig. 7 is a view partly in side elevation and partly in section of a certain clutch throwing arm, an arm actuating rod andthe connections there-, between, Fig. 8 is an elevation of the parts seen in Fig. 7 looking in the direction of the arrow 8, and Fig. 9 isa View partly in section of a slightly-modified form of'connecting device'between the clutch throwing arm and arm actuating rod. A

Referring 'to said" drawings, which'illustrate a simple embodiment of the invention applied to an automaticdie press of the type illustrated in the above mentioned patents,

the reference character 10 designates the press body, 11 the table for holding the metal strips,and 13 the feed way into which metal strips are inserted by suitable strip inserters (not shown),

The feed way hasa stationary side wall 16, 16 ;and a movable side wall 18, the'latter being pivotally secured to the base portion 22 of the table 11 (see Fig. 6) by arms 19, whereby'the movable side wall 18 may be swungback to expose the feed way for any purpose. Projecting into the feed way 18 are the fingers-17 of the finger bar mechanism and the bar 1-7-of said finger bar mechanism is reciprocated by mechanism so as to 'feed' the metal strip (with which the fingers engage in esuccession) in a step by step fashion toward the die mechanism (not shown). In theform illustrated, a slide block 36, sliding in guide ways in the table base22, is connected'to a connecting rod 35 by a connecting pin 44 secured in a lug 42 of the slide block and held in a stirrup portion 37 of the connecting rod by a spring pressed pin which is contained in a sockete'd lug 35, formed on the connecting rod 35, and bears against the connecting pin, 4 4. The stirrup 37 has anoffset portion 37 at one end, inwhich the connecting pin 44 is normally held by. the spring pressed pin 45. The arrangement is such that under normal conditions, when the connecting rod 35 is reciprocated, it recipro cates the slideblock 36 and therewith the finger bar 17 and: finger bar mechanism. Adjustable stop members 50, 51 are provided, one in front-of each end ofthe slide block, which act as stops for limiting any lengthwise movement of the slide block independent of the connecting. rod. The connecting rod is reciprocated by the usual actuating mechanism, as is well understood, well as by reference to my prior patents and; slide block above described, the mech anism described conforms generally to that illustrated and described in my prior patents above referred to. r

The mechanism for automatically stopping the pressin case of an abnormal condition in the feed way 13will now be described Projecting into the feed way is the setting elementof said mechanism. It is here shown ascomprisinga pin having one end projecting into the feed way 13and standing in the path of movement offthe thin metal strips as they are being inserted into the feed way (seeFig. 6). Said pin 60 is slidahly mount.- ed in a bearing bracket 61 supported upon the table portion 22, and engageswvith one arm 6201: a lever 63 which is shown fulcrumed upon the bracket 61. toswing in a plane transversely to the feed way. The other arm 64 of the lever 63 is considerably longer than the arm 62, whereby any slight movement of the shorter arm will be multipliedmany times in the longer arm 64:. This is because the movement imparted to the pin 60 by the thin strip of metal is very slight, and a longer stroke of the long arm is thereby obtained, which in many forms of operating mechanism is required. In its present.v form the lever 63 is employed to open an airvalve of a vacuum line, or an air pressure line, which leads to the cylinder of a suitably constructed connecting device "other suitable source.

which operates to connect a continuously reciprocating rod with a clutchthrowing arm whenever the lever 63 is actuated.

7V \eferring now to Figs. 1 and'Q, a vacuum pipe 65 leads from a vacuum pump (not shown), and in case the die press is equipped with a vacuum pump," the pipe may lead therefrom, otherwise it may lead from any In the vacuum pipe 65 is interposed, an. air valve 66 which is normally closed. The valve 66 isplaced in a position in which its valve stem 67 will stand in front of the end of the long arm 6% of thelever 63, in position to be engaged thereby whenever the lever 63 is m ved. by the pin 60. lVhenever the lever 63, is moved by the pin 60, it actuates the valve stem and unseats the valve, thereby permitting the vacuarm connecting device and thereby setting. it

in active position for actuating the -clutch throwing arm. A vacuum pipe 68 connect ed to one side of the air valve 66 leads to said connecting device. tween the lever 63 and valvestem 67, anadj ustment stud 69 (see'Fig. 6) is threadedly secured in the end of the arm 64 of the lever 63. This adjustment. stud can beadjustednicely so as to make the action of the lever 63 very sensitive. It is to be understood that the parts are so adjusted that when one metal strip at a time is inserted into thefeed way, the lever 63 remains inactive and the air valve remains closed. hen, however, two or more strips are fed into the feed way as seen in Fig. 6, the pinv 60 is therebymoved endwiseto the left, as viewed inFig. 6, the long arm of the lever 63 thereby swungto the right, the valve stem depressed and the valve opened. Opening the vacuum line to the connecting device for the clutch throwing arm causes a detent to become intering mechanism, whereby said 'arm' is actuated in adirection to operate the clutch mechanism andstop the press mechanism.

The clutch'throwing arm 70, is secured upon one end of a rock shaft 71, which in the form of the invention illustrated,yextends through the press body and is'secured, atits other end, to the clutch throwing lever 72. A continuouslymoving element, as for instance a reciprocating rod73 is provided for actuating the clutch throwing arm 70 whenever an abnormal condition. arisesin thefeed way, said rod being normally disengaged from the clutchthrowing armand reciprocating freely with respect thereto. For reciprocating therod 73 I provide a cam block 74 on the crank shaft 9 of the press, which engages with an .arm 7 5 of a bell crank lever 76, or a roller thereon, the other end of the lever being connected to the To a'ltord adjustment be rod 73. Obviously, engagement of the rotating cam or cams of the cam block with the arm 7 of the bell crank lever 76 causes reciprocation of the rod 7 Other equivalent means may be substituted for the rod reciprocating means described, as is well understood and I do not wish to be understood as intending to limit myself to the exact form of means shown.

The rod 73 extends down to the clutch throwing arm 70 and passesloosely through a block 78 which is secured to and fulcrumed between the forks 79of the clutch throwing arm 70. On the lower end of the .1 rod 73 is a shoulder or stop member, 80,

here shown in the form of a block secured to. the rod 73 by a nut 81, threaded on the rod below the shoulder 80, and a set screw ranged to be moved into the path of moveinent of said shoulder, for engagement therewith, whenever an abnormal condition arises in the feed way.. In the form of means shown for actuating the detent 83, a'vacuum cylinder 84 is employed, which cylinder may be formed in the block 7 8, iif desired, and in said cylinder is a plunger 85 which is connected to the detent by arsteln 86. The detent and cylinder are shown as extending in a direction generally parallel with the rod 73, and the detent is shown as formed with an arm 87, arranged at right; angles to the main body of the detent, and engaging with the stem 86 of the plunger 85. Downward movement of the". plunger in the cylinder acts to swing the lower end of the detent to the right (as viewed in Fig. '7) in position for engagement with the shoulder 80, on its up stroke. The vacuum pipe 68 leads from the vacuum cylinder 84 to the air valve 66, as has been heretofore explained. l/Vhenthe ailvalve is opened, a partial vacuum is created in the cylinder 84, the plunger 85 is drawn down therein, the detent swung into position for engagement with the shoulder 80 on the rod 73, which on its next up stroke, engages the detent, lifts it'and therewith the block 78, and swings the clutch throwing arm upward, which turnsthe rock shaft 71 and'swings down the starting lever 72, thereby. actuating the clutch and brake mechanism and stopping the press. As soon as the air valve 66 is closed, the vacuum is shut 01f, the detent moved to normal position and the hand lever, is again free to be manipulated tostart the press.

lVhenever a jam occurs in the feed way, movement of the fingerbar' 17 is arrested, and because of the-loose connections 37 44,

I 45, between the slide block 36 and connectby suitable fittings.

ing rod 35, the press mechanism is free to operate until stopped, and ordinarily the connecting rod 35 was therefore recip'rocated idly until the press was stopped, the jam removed and the press again started. In accordance with one phase of the present invention, whenever a jam occurs, and the pin 44 is thereby forced out of the inclined part of the slot in the stirrup 37, the automatic press stopping mechanism is set into action, and the press stopped. The means for accomplishing this result -will now be described. I

Referring to Figs. 1 to. 4, inclusive, it will be seen that the stirrup 37 has a slide block 90, bolted or otherwise secured to it, and which extends lengthwise of the stirrup.

Under normal conditions, said slide block reciprocates idly, but whenever the coupling 7 pin 44 isforced out of the inclined part of the slot of the stirrup, the stirrup and slide block are thereby moved laterally of the coupling pin 44, thereby bringing the slide block into a path of movement, wherein it actuatesvalve mechanism for unseating the valve of an air valve in the vacuum line running to the vacuum cylinder 84, and thereby setting in motion the automatic press stopping mechanism. In its present form, said means comprises aswinging arm or plate 91 fulcrumed on a bracket 92, secured to the table portion22, and lying contiguous with,

but out of the normal path of movement taken by the slide block 90, the arrangement or'the parts being such that when the coupling pin 44 is forced'out'of the inclined end of the slot ot'the stirrup and the latter thereby moved sidewise, the slide block 90 swings back the arm or plate 91, and opens an air valve 93 of the vacuum mechanism,-

as will be presently explained.

Leading from the vacuum line 65 is a A'lJlkll'lCl] pipe 96 leads from the air valve 93 to the pipe 68, to which it, is connected It will be observed from an inspection of Fig.2, that the vacuum pump is connected.

to one'sid-e of the airvalves 66, 93, hy the pipes, 65, 94, and that said valves are normally held in closed position. It will also be seen that the other side oi? said valves 66,

93 are connected to the vacuum cylinder 84 by the pipes 68, 96. If either air valve is opened, communication is established between the vacuum pump and vacuum cy1in der 84, through the air valve which was opened. I

From the above description'it is apparent that when two or'more thicknesses of strips way, the air valve 66 is opened,'and the auare placed at the same time in the, feed preferred form.

tomatic arm actuating mechanism for the clutch throwing arm. is set in motion, the arm is raised and the press stopped. It will also be apparent that if a jam occurs in the feed .way causing the linger bar to be blocked, that. the connection betweenthe linger bar and its actuating mechanism is automatically broken, the air valve 93 opened. and the press stopped through the instrumentality of the automatic press stopping mechanism. hen the excess strip or buckled strip is removed from the feed way, the press is started in the usual way by litting up on thestarting lever.

Inthe modified form shown in Fig, 9 of the connecting device between the clutch throwing arm and arm actuating rod, a compressed air cylinder8 l is shown, in which is aplunger connected to the detent 83 by a stem 81?. A compressed air pipe'68 leads from a suitable air compressor, not shown, to the compressed air cylinder 84f and supplies compressed air to said cylinder. The other parts of the device are substantially like those shown in the It is obvious that when either of the valves, which. in this case are interposed in the pipe 68 between the air compressor and the compressed air cylinder 84, is opened the plunger 85 will be moved in a direction to throw the detcut 83' into engagement with the shoulder 80 on the clutch actuating rod 73 on its next up stroke.

More or less variation of the exact details of construction is possible without departing from the spirit of this invention; I desire, therefore, notjto limit myself to the exact form of the construction .shown and described, but intend, in the following claims, to point out all of the invention disclosed herein.

I claim as new, and desire to secure by Letters Patent:

1. In an automatic die press, the combina tion with a feed way for the work, finger bar mechanism, associated therewith, finger bar actuating mechanism, and clutch throwing mechanism for starting and' stopping the press, of a normally inactive clutch throwing arm, a block having a. vacuum cyl inder therein and carried by said arm, and having a vacuum plunger therein, a reciproeating arm actuating rod guided in said block, and having a shoulder thereon, a detent mounted on said block for engagement with said shoulder on the rod,'and' opera tively connected to said'vacuum plunger, a vacuum pipe leading to said vacuum cylinder, a normally closed air valve in said vacuum pipe, and sheet actuated emergency mechanism arranged to open said valve.

2. In an automatic die press, the combination with a feed'way for the work, finger bar mechanism, associated therewith, finger bar actuating mechanism, and clutch throwing mechanism for starting and stopping the press, of a normally inactive clutch throwing arm, a. block having a vacuum cylinder therein a'ndcarried by said arm, and'having a vacuum plunger therein, a reciprocate ing arm actuating rod guided in said block, and having a. shoulder thereon, a. detent mounted on said block "for engagement with said shoulder on the rod, and operatively connected to said vacuum plunger,'a vacuum pipe leading to said vacuum cylinder, a strip engaging element extending into said "teed way, an air valve in said vacuum pipe, and, valve operating connections between said strip engaging element and valve.'

3. In an automatic die press, the combination with a continuously moving press element, a feed way for the work, sheet feeding mechanism, and clutch throwing mechanism for starting and stopping the press, of normally inactive emergency press stopping mechanism, comprising an emergency press stopping element directly'operated by said continuously moving press'element and arranged for operative conection with said clutch throwing mechanism, but normally unconnected the1'ewith,,a normally inactive movable member, made operative solely under the influence of an abnormal condition in the feed way, ando 3erat1ve connections bet-ween said normally inactive movable member, and said emergency press stopping element for operatively connecting the latter element with said clutch throwmg mechanism. Y

4-. In an'automatic die press, the combination with a continuously moving press element, 9. feed way for thework, sheet feeding mechanisnn: and clutch throwing mechanism for starting and stopping the press, of normally inactive emergency press stopping mechanism, comprising an emergency press stopping element directly operated by said continuously moving presselement and arranged for operative connection with said.

clutch throwing mechanism, but normally unconnected therewith, a normally inactive movable member, made operative solely under the influence of an abnormal condition in the feed way,pn'eumat1c means for operatively connecting said emergency press stopping element with said clutch throwing mechanism, said pneumatic means including an air line, and an air valve in said air line and actuated by SELlClIlOI'HlZIllY inactive movable member.

5. In an automatic die press, the combina= tion witha feed way for the work, sheet ieedmg mechanism, embodying two connectible and disconnectible members, one of which is a driver and one a drivenelement,

said driver capable otmovement independently of the'd-riven member, and'having a I normally inactive actuating member which ismade actlve whenever'the driver is disconnected from the driven element, anemergency clutch actuating member, normally inactive mechanism for actuating said emer gency clutch actuating member, and means for setting into action said normally inactive mechanism, operated by said actuating member of the connectible and disconnectible driving and driven members.

6. In an automatic die press, the combina tion with a feed Way for the work, sheet feeding mechanism, embodying two connecterating to set into action said normally in-- active mechanism for actuating the clutch actuating member. 7

7 In an automatic die press, the combination with a feed way for the work, sheet feeding mechanism, embodying two connectible and disconnectible members, one of which is a driver and one a driven element, said driver capable of movement independent of the driven member, and having a normally inactive valve actuating member which is made active whenever said driver is disconnected from the driven element, power mechanism, starting and stopping mechanism therefor, an emergency power disconnecting member, normally inactive mechanism for actuating said emergency power disconnecting member, including a vacuum operated arm connecting mechanism, a vacuum pipe leading to said arm connecting mechanism, and a valve in said vacuum pipe ar 'anged to be actuated by said valve actuating member. v

8. In an automatic die press, the combination with a feed way'for the work, sheet feeding mechanism including a finger bar and a connecting rod having a stirrup and pin connection with the finger bar, said stirrup being capable of lateral movement relative to said pin connection whenever disconnected from said pin, an air valve arranged to be actuated by said stirrup whenever it is disconnected from said pin, a vacuum line in which said air valve is interposed, and emergency clutch throwing mechanism having a vacuum' operated element on said vacuum line, for setting into action said emergency clutch throwing mechanism.

9. In an automatic die press, the combination with a feed way for the work, sheet feeding mechanism including a finger bar and a connecting rod having a stirrup and a pin connection with the finger bar, said stirrup having an inclined slot for affording lateral movement relative to said pin connection whenever disconnected from said pin, a slide block on said stirrup, an air valve arranged to be actuated by said slide block whenever the stirrup is disconnected from said pin, a vacuum line in which said air valve is interposed, and emergency clutch throwing mechanism having a vacuum operated element on said vacuum line, for setting into action said emergency clutch.

throwing mechanism.

CHARLES D. MCDONALD. 

